1. Field of the Invention
The present invention relates to the field of construction elements. In particular, the present invention provides an improved concrete block useful for constructing above and below grade walls.
2. Description of the Related Art
In applicant's issued U.S. Pat. No. 6,226,951, a robust concrete block is disclosed. Each block has a front panel, a rear panel, and webs that connect the front and rear. The blocks are notched at their ends to interfit and have complementary top and bottom profiles that also interfit. The blocks can be assembled without the aid of mortar, using specially designed corner blocks, into wall structures that can then be filled with concrete, resulting in a substantially monolithic concrete wall structure. The present invention is an improvement on the blocks described in U.S. Pat. No. 6,226,951 in that it provides an improved design allowing for freer flow of concrete into the wall structure and improved interlocking ends that will effectively anchor the blocks in place after concrete is poured.
A modified interlocking end structure for dry stack blocks is shown in applicant's U.S. Pat. No. 6,591,569. In that patent, the blocks are provided with substantially Z shaped ends, to facilitate close end to end alignment of the blocks. Corner blocks with complementary Z shaped portions near the ends of their side panels are provided. The blocks of U.S. Pat. No. 6,591,569 fit together extremely well due to the interlocking of the Z shaped ends. However, the ends tend to be more fragile than is desirable, because the end wall is diagonal. The present invention overcomes this drawback, and provides a block with the effective interlock shown in U.S. Pat. No. 6,591,569, but without the end wall weakness. Moreover, the corner blocks of the present invention present flatter surfaces, and therefore they stack more effectively for shipping.